How to Lay Thin Pavers Over Concrete Without Mortar

You can install pavers over concrete with light cracks, but not if the cracks are spreading rapidly.

Concrete patios serve their purpose well, but the plain material adds little interest to your outdoor space. Removing the concrete and replacing the patio with pavers involves laying a compacted gravel base layer. However, this isn't necessary because you can lay the pavers directly over the concrete. Without mortar, you can lay a sand base to absorb impact and prevent thin pavers from cracking. Patios typically require edging to hold pavers in place, but pavers that are 1 inch thicker can work as a stabilizing perimeter for the rest of the pavers.

1

Mow the grass and trim the edges around the concrete patio, then sweep away all grass clippings so you have better access to the perimeter. Clean the concrete with mild detergent and a scrub brush; use a degreaser to lift tough oil-based stains, if needed. Rinse the soap and allow the patio to dry.

2

Measure the width of the border pavers; while these can be the same material as the thin pavers in the center of the patio, they must be about 1 inch thicker. Mark a chalkline around the perimeter of the patio to the same width as the border pavers.

3

Apply the border pavers directly to the concrete perimeter with polyurethane construction adhesive that you squeeze onto the concrete and the bottom and sides of the pavers. Follow the chalk lines as a guide for border paver placement, and place the pavers as tightly together as possible. Leave one side of the patio without border pavers to allow more room to lay the thinner pavers on the inside.

4

Cover the area inside the border pavers with landscaping fabric.

5

Spread a 1-inch layer of masonry sand over the landscaping fabric. Drag a scrap piece of wood as a screed to spread the sand in an even layer. Lay a level across the sand in several places to ensure the sand is level.

6

Lay the thin pavers over the sand bed, starting at one of the corners closest to the house and working your way from side to side. Lay the pavers with the joints overlapping. Cut a score line across pavers with a cold chisel and brick hammer, than place a bolster chisel in the score line and hit the bolster chisel to break the paver in two pieces, to fit in small spaces. You can step on the pavers as you fill in the area, but do not step in the sand bed.

7

Glue the border pavers to the fourth side of the patio with construction adhesive after you have set all the thin pavers in place. Ensure that the border pavers are pushed tight against the thin pavers to prevent shifting.

8

Run a plate compactor over the entire patio in two directions to set the pavers into the sand base. If the thin pavers are slightly higher than the border pavers, the plate compactor can settle them into the sand for an even height across the entire patio.

9

Sweep polymeric sand into the cracks between the pavers to help bond the pavers together. Unlike masonry sand that can quickly wash out of the cracks, polymeric sand hardens after it gets wet.

Things You Will Need

Broom

Mild detergent

Scrub brush

Degreaser

Measuring tape

Chalk line

Polyurethane construction adhesive

Landscaping fabric

Masonry sand

Scrap two-by-four

Cold chisel

Brick hammer

Bolster chisel

Plate compactor

Polymeric sand

Tip

This project only works on a patio beside a house if the threshold into your house is high enough off the ground to accommodate the paver thickness, plus an additional one-half to 1 inch of height to allow for frost upheaval, if frost is a frequent problem in your area.

If this is your first time working with pavers, you might find it easier to set the border pavers in place before applying the construction adhesive.

About the Author

A former cake decorator and competitive horticulturist, Amelia Allonsy is most at home in the kitchen or with her hands in the dirt. She received her Bachelor's degree from West Virginia University. Her work has been published in the San Francisco Chronicle and on other websites.